docs(satp-hermes): add example for cross-chain transfers of NFTs

[AndreAugusto11]

The satp-demo repository should have a working example for the cross-chain transfer of NFTs.

To be done:

• Development of an NFT smart contract in the EVM folder
• Addition of a new folder with case 8 with the scripts, and explanation
• Addition of this script to the main Makefile
• an example of satp configured with 3 leafs with a pre deployed bridge. configure gateway to load configuration of deployed bridge

[AndreAugusto11]

@Tomas-Silva2187 pls note that the repository has been migrated to the Cacti Demos repo. When implementing this feature, open a PR in this new one pls.